Wired Intelligent Edge

 View Only
last person joined: 7 hours ago 

Bring performance and reliability to your network with the HPE Aruba Networking Core, Aggregation, and Access layer switches. Discuss the latest features and functionality of your switching devices, and find ways to improve security across your network to bring together a mobile-first solution
Back to discussions
Expand all | Collapse all

One Vlan Multiple Subnet DHCP Problem

This thread has been viewed 31 times

  • 1.  One Vlan Multiple Subnet DHCP Problem

    Posted Nov 12, 2021 10:53 AM
    Hello ;

    I want to use 4 diffrent subnet in a vlan on ArubaOs-Cx series switch. The configuration is as follow .

    interface vlan 2
    vsx-sync active-gateways mgmd
    ip address 192.168.1.1/24
    ip address 192.168.2.1/24 secondary
    ip address 192.168.3.1/24 secondary
    ip address 192.168.4.1/24 secondary
    active-gateway ip mac 00:00:00:00:02:00
    active-gateway ip 192.168.1.1
    active-gateway ip 192.168.2.1
    active-gateway ip 192.168.3.1
    active-gateway ip 192.168.4.1
    ip helper-address 192.168.168.1

    Here I just want to distribute IP from 192.168.4.1/24 subnet . Do you need an extra config here? In this state, I can't get IP from dhcp.



    ------------------------------
    ilhan �i�ek
    ------------------------------


  • 2.  RE: One Vlan Multiple Subnet DHCP Problem

    Posted Nov 13, 2021 10:07 AM
    You probably need to have:
    ip address 192.168.4.1/24
    ip address 192.168.1.1/24 secondary

    Services like ip-helper will always use the interface address, and then the DHCP-server will see the relayed request coming from 192.168.1.1.
    I would use 192.168.0.1/22 as my gateway address if I needed the address space.

    ------------------------------
    Arne Opdal
    ------------------------------

    Original Message


  • 3.  RE: One Vlan Multiple Subnet DHCP Problem

    Posted Nov 13, 2021 11:02 AM

    Here, as an example, I wrote subnets like this. I can't do /22 on the subnet that I need to give. As far as I understand, in such a structure, I can only distribute ip from the first subnet.
    ------------------------------
    ilhan �i�ek
    Network Engineer
    ------------------------------

    Original Message


  • 4.  RE: One Vlan Multiple Subnet DHCP Problem

    EMPLOYEE
    Posted Nov 15, 2021 02:38 AM
    Hello, 
    I think what you need here is the command ip bootp-gateway

    Configuring a BOOTP/DHCP relay gateway
    The DHCP relay agent selects the lowest-numbered IP address on the interface to use for DHCP messages.
    The DHCP server then uses this IP address when it assigns client addresses. However, this IP address may
    not be the same subnet as the one on which the client needs the DHCP service. This feature provides a way
    to configure a gateway address for the DHCP relay agent to use for relayed DHCP requests, rather than the
    DHCP relay agent automatically assigning the lowest-numbered IP address.

    Please try to configure ip bootp-gateway to be the VLAN address in 192.168.4.0/24

    switch(config)# interface vlan 2
    switch(config-if)# ip bootp-gateway 192.168.4.1

    For reference ArubaOS-CX IP services guide

    https://www.arubanetworks.com/techdocs/AOS-CX/10.08/PDF/ip_services_6300-6400.pdf

    ------------------------------
    Emil Gogushev
    ------------------------------

    Original Message